427 LS1 turbo selection..
maybe sell the 427 block, use the 60-1's on the stock engine, plus a forged rotating assembly is the way to go?
maybe sell the 427 block, use the 60-1's on the stock engine, plus a forged rotating assembly is the way to go?

You have done the math, and you know what your goals are.
If this is a street car, you want the SMALLEST turbos you can get away with to give you the best street manners possible. Turbo lag is the enemy.
I would also go with ball bearing turbos. You might want to call up precision and talk to them about their new air cooled ball bearing turbos.
I hate to say it, but I do not think you are going to find the information you are looking for here... I have been here for a while and from what I have seen most people just slap on a turbo and go without much consideration to street manners.
-twin 60-1 with .81 A/R exhaust housings @15 lbs should make at least 800-850 rwhp.
-custom turbo cam in the 230's intake / 220's exhaust on a 117
Give us a call if you need more info.
Rob.
416 751-8047
Twin Turbonetics 62-1 with the .81 a/r would be perfect.
The 62-1 feeds about 10% more air than the 60-1.
Maxes out at about 62 lbs/min
427 running 6,500rpm and 85% Ve at 15psi will need 100-120 lbs/min
and will easily make 800-900rwhp.
So (2) 62-1's should work nice. With the .81 a/r that Turbonetics offers
you will get a little better spool than the .96 a/r.
If you dont care about breaking 1000rwhp, then you have a really good plan.
As for the 806 heads, I agree 100% on upgrading to AFR225's.
Champion, the cam specs you've mentioned seem a bit of reverse logic from what I have seen so far. My understanding is, the more lobe separation, the less street friendly. Also the intake and exhaust numbers are reversed. It seems to me that a longer exhaust duration would increase performance based on valve sizing and lift; especially with little to no overlap. Am I thinking correctly?
The Best V8 Stories One Small Block at Time
You have done the math, and you know what your goals are.
If this is a street car, you want the SMALLEST turbos you can get away with to give you the best street manners possible. Turbo lag is the enemy.
I would also go with ball bearing turbos. You might want to call up precision and talk to them about their new air cooled ball bearing turbos.
I hate to say it, but I do not think you are going to find the information you are looking for here... I have been here for a while and from what I have seen most people just slap on a turbo and go without much consideration to street manners.
Feel free to add specifics rather than just make general comments about the site in general and the lack of knowledgeable people wandering about aimlessly within.
As for the 806 heads, I agree 100% on upgrading to AFR225's.
Champion, the cam specs you've mentioned seem a bit of reverse logic from what I have seen so far. My understanding is, the more lobe separation, the less street friendly. Also the intake and exhaust numbers are reversed. It seems to me that a longer exhaust duration would increase performance based on valve sizing and lift; especially with little to no overlap. Am I thinking correctly?
Have you been getting my PMs? I have not heard back from you.

So Killer, you're still adamant about the 60-1's being far too small for the 427 application? It looks like, as far as a twin setup is concerned, that t70's would work much better; any thoughts on the single vs twin option? I think there's an s91 and also an s480 up for sale right now in the classifieds.
I definitely appreciate all your inputs.. like I said, I am popping so many cherries with this project.. but, eat an elephant one bite at a time right?
If you think you will ever get the itch to bust 1000rwhp then I would
do some a pair of Precision 67's ..... if 800-900rwhp is more than enough
to scare the crap out of you then a pair of 62's will do that easy, cost less
and spool better.
If it was my build ......
402-408 @ 9.0 c/r
225 ported heads
Custom turbo cam
1 3/4 primary turbo headers
twin 3" downpipes
twin Tial 44mm wategates
Twin Garrett GT4088's
http://www.turbobygarrett.com/turbob...8_703457_2.htm
Make 850 at low boost and well over 1100+rwhp at the push of a button
Zoom

r.barn... I'm not sure what's going to "scare the crap" out of me.. I know that after laying my bike over last summer(lots of fractures and road rash involved) I'm a bit skiddish on curves, no matter what I'm in.. but as far as straight line, nothing thrills me more than to be slammed into the seat when I hit the throttle.
I honestly would like to stop when I am required by NHRA to have a parachute.. boost, motor, spray, whatever it takes.. parachute is the goal.
Do it right the first time because Turbo is addiction and YOU WILL UPGRADE your Turbos down the road.
Good luck with your build man
1) keep the turbos and go to less cubes.
2) keep the motor and go to bigger twins
3) keep the motor and go to a big single
Either way, buy a good set of aftermarket heads with a thick deck.
Personally, I'm very budget minded so I would go for most bang for the buck depending on what's available out there.
As for the S480 vs the S91. Both those turbos would work great. The S91 would make a good bit more power but either will get you to your goal. The 480 should be alot cheaper.
The S91 is overkill, but the S480 would be just right.


